lol! I have had many L7's & L5's. Used them and abused them, still don't like them any more than their round cousins. I will add that the 12's in my avitar were pushed by a Infinity 1600.1 referance and they did a 141db on the term lab.
how accurate is the power handling that they claim on the website?
I have burped a L7 with a BXI2600 and it took it pretty well. The amazing part was the little amount of excursion it had. They may claim that square is better because it has more cone area than asimilar sized round sub, but the cone needs to travel inorder to push more air. I gave up on them, maybe you can have better luck untill you stop using them?